Science comes to life for Afton-Lakeland fifth graders

October 09, 2017
students check out aquaponic system

It might just look like a normal fish tank in the corner, but fifth grade students at Afton-Lakeland Elementary will tell you there is a whole lot more going on in their science classroom than meets the eye.

“The big box on top is a grow bed, and a pump is running constantly to pump water into the grow bed,” one student explained.

“It uses a bell siphon,” added another student. “When the grow bed is full of water the siphon drains and makes a burp sound. Then it sucks in air instead of water.”

The fifth graders are learning about ecosystems and water cycles in a fun and interactive way - by creating their very own self-sustaining aquaponic system to grow fish, herbs and vegetables in their classroom.

The system features a large aquarium with several fish (crayfish are coming soon), a grow bed to house the plants, a full spectrum light to mimic the sun, and filters and a siphon to transfer water and nutrients between the two. While four bluegill sunnies swim around, a fifth Plecostomus (or sucker fish) goes about cleaning the tank. In the grow bed, herbs like rosemary, basil, sage and thyme are growing along with carrots, potatoes, blackberries, raspberries, ginger, zinnias, and a lone cactus.

“It’s an ecosystem where everything helps everything else- the plants, fish, even the bacteria are helping each other.  The only input is fish food and water top ups,” explained teacher Mike DeRuyck.

The aquaponics system allows fish and plants to grow together in one integrated system. The fish waste provides an organic food source for the plants, and the plants naturally filter the water for the fish. Bacteria are also present, converting ammonia from the fish waste into nitrates to help the plants grow.  

It’s the perfect environment for students to see science at work firsthand. They’re learning about sustaining ecosystems, observing and measuring the plants while they grow, testing water quality and even studying principles of physics and mathematics by considering how the siphons pump water.

“I don’t even have to figure out how to weave science lessons into this, it’s so easy,” DeRuyck said. “Fifth grade science is focused on earth science and life science, and this just fits perfectly.”

Students helped develop the plans for a aquaponics system several years ago, and it made its first appearance in his classroom last year. He’s added more components for students this year, and is hoping to receive a grant to grow the system even bigger in years to come.

“I like it because it’s very interactive and fun,” said Izzy Siefert, a fifth grade student. “I really like the fish! I look at it and it is always so interesting.”